Medical retrieval device with independent rotational means

ABSTRACT

A medical retrieval device used to remove objects such as urinary and biliary calculi from the body comprising a handle assembly with an independent rotational means, a sheath, and an object entrapping assembly. In preferred embodiments, the handle assembly comprises a longitudinally stationary base portion and a thumb slide actuation means. The longitudinally stationary portion comprises a handle base and a rotating means. In a preferred embodiment, a portion of the thumb slide actuation means is located between the distal and proximal ends of the handle base portion during the complete actuation cycle. Actuation of the thumb slide relative to the handle base causes the object entrapping assembly to be actuated between the open and closed positions. Rotation of the rotating means relative to the handle base causes precise rotation of the object entrapping assembly. The thumb slide actuation means and rotating means are separate and independent of each other, preventing inadvertent adjustment of the degree of actuation during rotation and preventing inadvertent adjustment of rotational position during actuation.

[0001] This application claims priority to U.S. Provisional ApplicationNo. 60/303,114, entitled Medical Device Handle with Rotational Feature,with Mark R. Bilitz as the inventor, and filed on Jul. 5, 2001. Thisapplication is also related to design Pat. No. U.S. 457,955 S, issuedMay 28, 2002, invented by Mark Bilitz and to the utility patentapplication entitled, Medical Retrieval Device With Cable ProtectionMeans, filed on Jul. 3, 2002, with inventors Stuart J. Lind and Mark R.Bilitz. The above applications are incorporated herein by reference.

BACKGROUND

[0002] 1. Field of Invention

[0003] This invention relates to medical retrieval devices for removingobjects from a body, particularly calculi from the urinary and biliarysystems.

[0004] 2. Description of Prior Art

[0005] Medical instruments are currently in use which reduce theinvasiveness and potential trauma previously associated with variousmedical procedures. One such procedure is the removal of objects, suchas kidney stones and gallstones, from the body. Various surgical devicesare available which allow objects to be removed from the body withoutrequiring major surgery. One type of surgical device is a mechanicalretrieval device. Typically, such instruments consist of 2 or moreflexible elements that are joined at their proximal ends and may or maynot be joined at their distal ends. The flexible elements are formed inthe shape of a basket, cage, grasper, or other entrapping configuration.This basket is attached to a drive wire that passes through the lumen ofa small diameter (typically 2.3 mm (7.0 Fr) or less) flexible sheath,which is usually greater than 50 cm in length. The proximal ends of thesheath and drive wire are attached to a multi-part handle, normallyconstructed of thermoplastic materials, which can typically be operatedby the user with a single hand. By manipulating the handle, the drivewire can be pulled back relative to the sheath, collapsing the basket asit retracts into the sheath. In this closed position, the sheath can bepassed through the working channel of an endoscope to the proximity ofthe object to be removed within the patient's body. The basket isexpanded to the open position by manipulating the handle, which remainsoutside the endoscope and the patient's body. The device is thenmanipulated using the handle until the object becomes enclosed withinthe basket. This manipulation may include advancing, withdrawing and/orrotating the basket in order to get the object to pass between theflexible elements that comprise the basket. When the object has beensuccessfully engaged within the basket, the endoscope and the retrievaldevice containing the object are then simultaneously removed from thebody.

[0006] A number of designs for the handle of medical retrieval devicesare in use. Typically, these handles consist of two main elements, ahandle base and an actuation mechanism. The sheath is attached to one ofthese elements, and the drive wire is attached to the other. By movingthe actuation mechanism relative to the handle base, the basket can beretracted into the sheath and extended from it. The handle design thatappears to be preferred, based on actual current use and sales volumes,is of a thumb slide design. This design features a main handle base thatremains stationary and a thumb slide actuator that slides along aportion of the handle body and has a thumb pad. This handle is held inone hand by wrapping the four fingers of the hand partially around thehandle base. The thumb of the same hand is placed on the thumb pad. Thedevice is actuated in one direction by moving the thumb pad away fromthe proximal end of the handle base, and in the other direction bymoving the thumb pad toward the proximal end of the handle base. Thistype of handle can normally be held in such a way that the range ofmotion of the thumb required to fully actuate the device is located in anatural and comfortable area near the thumb's resting position. Sinceconsiderable skill and dexterity can be required of the user in order toretrieve an object, user comfort is of primary importance.

[0007] There are many variations of the thumb slide handle in use.However, these and other prior art handle designs do not have amechanism for rotating the basket to facilitate capturing the object.Rotation can only be accomplished by rotating the entire handle. Thismethod has a number of disadvantages. By rotating the entire handle, theuser must accordingly rotate their hand. Since the hand would initiallybe placed in a natural position, the position of the hand after rotationwould not necessarily be comfortable for further manipulation of thehandle. Again, user comfort is significant due to the considerable skilland dexterity needed to successfully complete a stone retrievalprocedure. Additionally, since the entire handle must be rotated inorder to rotate the basket, the sheath must rotate as well as the drivewire. This is a disadvantage because the friction between the sheath andthe endoscope's working channel can prevent a smooth 1:1 torque ratiobetween the handle and the basket. This is particularly relevant whenthe endoscope is flexible and is in an articulated position. Lack ofprecise rotational control can increase the difficulty of engaging theobject in the basket, thereby lengthening the procedure.

[0008] Certain handle designs have been used which allow rotation of thebasket without rotating the entire handle and thus the sheath as well.U.S. Pat. No. 4,046,150 (1977) to Schwartz et al. discloses a retrievalbasket with such a handle. This handle has a first member that isattached to the sheath. A second member, which is attached to the drivewire, is located at the proximal end of the first member. The device isactuated by sliding the second member into and out of the first member,which is held stationary. The basket is rotated relative to the sheathby rotating the second member relative to the first member. However,this handle is not of the preferred thumb slide style, and requires theuse of two hands to actuate. Also, the actuational and rotationalcontrols are not independent of each other.

[0009] U.S. Pat. No. 5,957,932 (1999) to Bates et al. discloses aretrieval basket with yet another type of handle. This handle is of apistol grip style, with a control knob located at the proximal end ofthe handle. The sheath is attached to the main body of the handle, andthe drive wire is attached to the control knob. The device is actuatedby pulling the control knob out from the main body of the handle andpushing it in. The control knob can also be rotated to rotate thebasket. When the trigger portion of the handle is squeezed, mechanicaladvantage is applied to the actuation of the device. This design hasseveral disadvantages. It requires two hands for normal actuation. Andsince the control knob is used for both actuation and rotation of thebasket, the actuation and rotation are not independent of each other. Italso uses a larger number of parts than other handle designs and istherefore is more complex and more expensive to manufacture. The abovepatents to Schwartz and Bates are incorporated herein by reference.

[0010] Another type of prior art handle, which is not referenced in anypatents, is shown in FIGS. 7 and 8. A handle assembly 190 consists of astationary portion or handle base 110 and a thumb slide 130 with a thumbpad 131. Handle base 110 has a distal end 181, a proximal end 182, and alength 180. Thumb slide 130 fits partially within handle base 110 andextends out from distal end 181, with thumb pad 131 remaining beyonddistal end 181. A hollow tube or sheath 150 has a working length 186 andis attached to thumb slide 130. A drive wire (not shown) passes throughthe lumen of sheath 150 attaches at the proximal end to handle base 110and at the distal end to a basket 160. To operate this device, handlebase 110 is held in one hand with the four fingers of the hand. Thethumb of the same hand is placed on thumb pad 131. When the thumb isextended away from the hand, thumb slide 130 slides out from distal end181 of handle base 110. This results in the device being in the closedposition, as shown in FIG. 7. When the thumb is pulled back toward thehand, thumb pad 131 slides toward distal end 181 of handle base 110.This results in sheath 150 being pulled back to expose basket 160. Whenthumb pad 131 is pulled back completely to handle base 110, the deviceis in the open position, as shown in FIG. 8. To rotate basket 160,handle base 110 is rotated relative to thumb slide 130. This design hasthe disadvantage that the actuation mechanism and the rotation mechanismare not independent. Both actuation and rotation are achieved bymovement of the thumb slide and the handle base relative to each other.This design also has the disadvantage that the thumb pad is locatedbeyond the distal end of the stationary handle base. This is adisadvantage because manipulation of the thumb slide is done with theuser's thumb extended away from the hand in a somewhat awkward position,which results in less than ideal tactile control over the actuation ofthe device.

[0011] The prior art handle designs that do allow rotation of the basketwithout rotating the entire handle have the disadvantage that therotation mechanism and actuation mechanism are not independent. As aresult, while the basket is being rotated, it may be inadvertently andundesirably expanded or retracted, or while it is being expanded orretracted, it may be inadvertently and undesirably rotated. Theretrieval of an object from within a patient's body using an endoscopeand a retrieval device is a precise and delicate procedure that requiresconsiderable user skill and dexterity. Since the user's control of thebasket is limited by the handle of the device, it is desirable that thehandle allows precise and independent control of both the actuation androtation of the basket, and is comfortable to use.

SUMMARY OF THE INVENTION

[0012] A medical retrieval device used for extracting objects such asurinary and biliary calculi from the body comprising a handle assemblywith an independent rotational means, a sheath, and an object entrappingassembly. In preferred embodiments, the handle assembly comprises alongitudinally stationary base portion and a thumb slide actuationmeans. The longitudinally stationary portion comprises a handle base anda rotating means. In a preferred embodiment, a portion of the thumbslide actuation means is located between the distal and proximal ends ofthe handle base portion during the complete actuation cycle. Actuationof the thumb slide relative to the handle base causes the objectentrapping assembly to be actuated between the open and closedpositions. Rotation of the rotating means relative to the handle basecauses precise rotation of the object entrapping assembly. The thumbslide actuation means and rotating means are separate and independent ofeach other, preventing inadvertent adjustment of the degree of actuationduring rotation and preventing inadvertent adjustment of rotationalposition during actuation.

[0013] An object and advantage of preferred embodiments of the inventionis to provide a medical retrieval device with a mechanism for preciselyrotating the basket that is independent of the actuation mechanism.

[0014] An object and advantage of preferred embodiments of the inventionis to provide a medical retrieval device with a mechanism for rotatingthe basket that cannot inadvertently cause adjustment to the degree ofactuation during rotation.

[0015] An object and advantage of preferred embodiments of the inventionis to provide a medical retrieval device that permits rotation of thebasket without requiring rotation of the entire handle assembly and/orthe sheath.

[0016] An object and advantage of preferred embodiments of the inventionis to provide a novel handle for a medical retrieval device that is of athumb slide actuated type that is comfortable for the user to hold andoperate.

[0017] An object and advantage of preferred embodiments is to provide anovel handle for a medical retrieval device that uses a minimal numberof parts, reducing cost and simplifying assembly.

[0018] Further objects and advantages of preferred embodiments of themedical retrieval device described herein are that such preferredembodiments are safe, reliable, and easy to use. Still further objectsand advantages will become apparent from a consideration of the ensuingdescription and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is an isometric view of the preferred embodiment of thepresent invention.

[0020]FIG. 2 is an exploded isometric view of FIG. 1.

[0021]FIG. 3 is a top view of FIG. 1 showing the basket in theretracted, closed, or collapsed position.

[0022]FIG. 4 is a top view of FIG. 1 showing the basket in the extended,open, or expanded position.

[0023]FIG. 5 is a bottom view of FIG. 1 showing the basket in theextended, open, or expanded position.

[0024]FIG. 5A is a cross sectional view of FIG. 5 taken on line A-A.

[0025]FIG. 5B is a cross sectional view of FIG. 5 taken on line B-B.

[0026]FIG. 6 is a side view, partially in section along the longitudinalaxis, of the handle assembly portion of the medical retrieval device inFIG. 1.

[0027]FIG. 6A is an enlarged view of the proximal portion of the handleassembly in FIG. 6.

[0028]FIG. 6B is an enlarged view of the mid portion of the handleassembly in FIG. 6.

[0029]FIG. 6C is an enlarged view of the distal portion of the handleassembly in FIG. 6.

[0030]FIG. 7 is side view of a prior art medical retrieval deviceshowing the basket in a retracted position, the top view and bottom viewbeing the same.

[0031]FIG. 8 is a side view of the same prior art device in FIG. 7 butshowing the basket in an extended position, the top view and bottom viewbeing the same.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0032] FIGS. 1 to 6C show a preferred embodiment of the invention. Amedical retrieval device has a handle assembly 90, which has alongitudinal axis 11. Handle assembly 90 is comprised of an elongatehandle base 10, a rotation means or spinner 20, a sliding portion orthumb slide 30, and a pin 40, all of which are preferably constructed ofthermoplastic materials. Handle base 10 has a proximal end 82, a distalend 81, and a length 80, which is between 5 and 20 cm. Handle base 10 isessentially hollow along longitudinal axis 11, with an internal bore andan opening 12 at distal end 81. A longitudinal slot having a narrowportion 14 a and a wide portion 14 b is located on the top surface ofhandle base 10. Wide portion 14 b has a proximal end 15 and a distal end16. Narrow portion 14 a extends from proximal end 82 of handle base 10to wide portion 14 b. Distal end 16 of wide portion 14 b is locatedproximal to distal end 81 of handle base 10.

[0033] Thumb slide 30 has a thumb pad 31 and a guide portion configuredas a fin 33, which has an upper portion 33 a and a lower portion 33 b.The width of upper portion 33 a of fin 33 is wider than the width ofnarrow portion of slot 14 a and narrower than the width of wide portionof slot 14 b. The width of lower portion 33 b of fin 33 is wider thanthe width of wide portion of slot 14 b. A through hole 32 passes throughlower portion 33 b of fin 33 longitudinally. Thumb slide 30 is locatedon handle base 10 with upper portion 33 a of fin 33 located within wideportion of slot 14 b and lower portion 33 b of fin 33 located within thehollow portion of handle base 10 below wide portion 14 b. With thumbslide 30 engaged with wide portion of slot 14 b in this manner, thumbslide 30 can be readily moved so that fin 33 is in any position withinwide portion of slot 14 b between proximal end 15 and distal end 16, butcannot inadvertently be removed vertically or longitudinally from wideportion of slot 14 b in handle base 10. Handle base 10 also limitsrotational movement of thumb slide 30. The total length of longitudinaltravel of thumb slide 30 relative to handle base 10 is preferably 5 cmor less. Thumb pad 31 is located between proximal end 82 and distal end81 of handle base 10. The actuation of thumb pad 31 overlaps the areabetween proximal end 82 and distal end 81 of handle base 10. A tube orsheath 50 has a proximal end 51, a distal end 52, and may be constructedof polyimide, PTFE, or other flexible material or combination ofmaterials, and has a lumen through its entire length. Sheath 50 has aworking length 86 that is preferably between 65 and 125 cm, and thediameter of sheath 50 is preferably approximately 1 mm or less. Sheath50 passes through opening 12, which is substantially larger in diameterthan sheath 50. Proximal end 51 of sheath 50 passes into through hole 32in thumb slide 30 and is secured to thumb slide 30 using adhesive orother means.

[0034] Spinner 20 has a knob portion 24 and a cylindrical portion 23that has a groove 22 extending around its circumference. Spinner 20 islocated at proximal end 82 of handle base 10, with cylindrical portion23 located within the hollow space of handle base 10 and knob portion 24of spinner 20 located at proximal end 82 of handle base 10. A hole 21 islocated in cylindrical portion 23 along longitudinal axis 11, andextends part way through spinner 20. Knob portion 24 of spinner 20 isaxially positioned, and has a diameter 79 that is preferably 1.5 cm orless. Pin 40 has a head 41 and a tip 42. Pin 40 fits snugly into a holein handle base 10, and tip 42 of pin 40 fits into groove 22. The lengthof pin 40 is such that when pin 40 is fully seated in the hole with head41 contacting handle base 10, tip 42 extends into groove 22 in spinner20, but does not fit snugly in groove 22. Thus spinner 20 is rotatablyattached to handle base 10. This configuration limits the longitudinalmovement of spinner 20 relative to handle base 10, but permits spinner20 to rotate freely about longitudinal axis 11 relative to handle base10.

[0035] A drive wire 70 has a proximal end 71 and a distal end 72. Anobject entrapping assembly or basket 60 is connected to distal end 72.Basket 60 consists of a number of outwardly disposed flexible elementsthat form a space for entrapping objects. Drive wire 70 may beconstructed or formed of stainless steel, nickel titanium alloy, oranother metal. Drive wire 70 slidably extends through the lumen ofsheath 50, with proximal end 71 of drive wire 70 extending past proximalend 51 of sheath 50. Proximal end 71 of drive wire 70 fits into hole 21in spinner 20 and is secured using adhesive or other means. Handleassembly 90 has a longitudinally stationary portion that compriseshandle base 10, spinner 20, and pin 40.

[0036] To operate the device, the user wraps four fingers of one handpartially around handle base 10, but not overlapping thumb pad 31. Thetip of the thumb of the same hand is placed on thumb pad 31. Referringto FIGS. 1 and 4, basket 60 is in the open or expanded position. In thisposition, thumb pad 31 is located at proximal end 15 of wide portion ofslot 14 b. To actuate the device to the closed or retracted position,the user extends the thumb outward from the hand while maintainingcontact between the thumb and thumb pad 31 and keeping handle base 10stationary in the hand. This action causes thumb slide 30 to slidewithin wide portion of slot 14 b toward distal end 16 of wide portion ofslot 14 b (arrow 55 a). This longitudinal movement of thumb slide 30relative to handle base 10 propels sheath 50 over drive wire 70 (arrow65 b). This enables longitudinal movement of sheath 50 relative tobasket 60, forcing basket 60 to collapse and become enclosed withinsheath 50. When thumb slide 30 rests at distal end 16 of wide portion ofslot 14 b, basket 60 is in the completely closed or retracted positionwithin sheath 50, as shown in FIG. 3. If, for example, the object thedevice is being used to retrieve is a ureteral calculus, the device isintroduced in this retracted position through the working channel of anendoscope into the ureter until the retracted basket emerges from thetip of the endoscope in the proximity of the calculus. The user thenpulls the thumb back toward the hand, sliding thumb pad 31 back towardproximal end 16 of wide portion of slot 14 b (arrow 55 a). This actionpulls sheath 50 back relative to drive wire 70 and basket 60 (arrow 55b). Basket 60 is then exposed and resumes its expanded shape, as shownin FIGS. 1 and 4.

[0037] Handle assembly 90 is then manipulated in order to entrap theobject within basket 60. Longitudinal manipulation of basket 60 relativeto the object is accomplished by pushing or pulling handle assembly 90along longitudinal axis 11. Rotational positioning of basket 60 isaccomplished by grasping knob 24 of spinner 20 with the thumb andforefinger of the user's second hand, and rotating spinner 20 aboutlongitudinal axis 11 (arrow 65 a), relative to handle base 10, which iskept stationary with the first hand. This causes drive wire 70 to rotatewithin sheath 50, and basket 60 to rotate relative to sheath 50 the sameamount in the same direction (arrow 65 b). Once the object has beenengaged within basket 60, the user then pushes thumb pad 31 forward partway toward distal end 16 of wide portion of slot 14 b until basket 60 ispartially closed in order to securely hold the object. The device andthe endoscope are then simultaneously withdrawn from the patient,holding thumb pad 31 stationary relative to handle base 10 to keep theobject secured within basket 60.

[0038] It can be seen from the above description that the medicalretrieval device according to this invention has a mechanism forprecisely rotating the basket that is independent of the extension andretraction actuation mechanism used to collapse and expand the basket.This permits rotation of the basket without requiring the user to rotatethe entire handle assembly, allowing for improved user comfort. Thisalso permits rotation of the basket without requiring the sheath torotate within the working channel of the endoscope, thereby allowingmore precise control of basket rotation. The handle base isolates thespinner from the thumb slide actuator. This prevents inadvertentlongitudinal actuation of the basket during rotation and inadvertentrotation of the basket during longitudinal actuation. It can also beseen that the handle assembly is of a thumb slide actuated type that iscomfortable for the user to hold and operate. It can further be seenthat the handle uses a minimal number of parts, reducing cost andsimplifying assembly. This gives the desirable result of a handleassembly of a preferred style that allows precise and separate controlof the actuation and rotation of the basket, and is comfortable for theuser to hold and operate.

[0039] Another aspect of the invention is the method of manufacturingthe medical retrieval device as described above. More specifically, themethod involves steps of injection molding a handle with the abovecharacteristics and assembling the device whereby the device has arotational means that is independent of and isolated from the actuationmeans.

[0040] Although the description above contains many specificities, theseshould not be construed as limiting the scope of the invention, but asmerely providing illustrations of some of the presently preferredembodiments of this invention. For example, the spinner may be attachedto the handle base by different means; a coaxial, dual sheath design maybe used; additional and/or alternative materials and joining methods maybe used; the handle assembly components may have other configurations ordimensions; other means may be used to control the distance of travel ofthe thumb slide; the thumb pad may only partially overlap the handlebase at part of its travel; a portion of the thumb slide may extenddistal to the handle base; the thumb slide and handle base may fittogether by different means; the sheath and/or drive wire may beremovable from the handle assembly; the basket may have otherconfigurations; the basket may be replaced with another type of tool,such as a grasping assembly or biopsy device; the device may be usedwithout an endoscope; objects other than those mentioned or in differentlocations in the body may be retrieved, etc.

[0041] Thus the scope of the invention should be determined by theappended claims and their legal equivalents, rather than by the examplesgiven.

What is claimed is:
 1. A medical retrieval device for extracting anobject from the urinary or biliary system comprising: a sheath and adrive wire each having a proximal end and a distal end, said drive wireslidably extending through said sheath, an object entrapping assemblyconnected to the distal end of said drive wire for entrapping saidobject, said sheath for collapsing said object entrapping assembly whenretracted into said sheath, and a handle assembly located at theproximal ends of said sheath and said drive wire, said handle assemblycomprising a base, a sliding portion and a spinner, said drive wire isconnected to said spinner whereby rotational movement of said spinnerrelative to said base enables rotational movement for positioning ofsaid object entrapping assembly relative to said sheath, said sheathconnected to said sliding portion whereby longitudinal movement of saidsliding portion relative to said base enables longitudinal movement ofsaid sheath relative to said object entrapping assembly for collapsingsaid object entrapping assembly when retracted into said sheath, wherebysaid handle assembly provides for independent rotational positioning andcollapsing of said object entrapping assembly.
 2. The medical retrievaldevice of claim 1 further including a thumb pad for actuating saidsliding portion, at least some portion of said thumb pad overlappingsaid base at some point during longitudinal actuation of said slidingportion.
 3. The medical retrieval device of claim 1 wherein length ofsaid sheath is about 50 centimeters or greater and at least some of saidsheath has an outside diameter of approximately one millimeter or less.4. The medical retrieval device of claim 1 wherein said base has alength between 5 cm and 20 cm.
 5. The medical retrieval device of claim1 wherein said spinner has a maximum diameter of 1.5 cm or less.
 6. Themedical retrieval device of claim 1 wherein said longitudinal movementof said sliding portion relative to said base is 5 cm or less.
 7. Themedical retrieval device of claim 1 wherein said base limits rotationalmovement of said sliding portion.
 8. The medical retrieval device ofclaim 1 wherein said base limits longitudinal movement of said spinner.9. The medical retrieval device of claim 1 wherein said drive wire isformed of nickel titanium.
 10. A medical retrieval device for extractingan object from the urinary or biliary system comprising: a sheath and adrive wire each having a proximal end and a distal end, said drive wireslidably extending through said sheath, an object entrapping assemblyconnected to the distal end of said drive wire for entrapping saidobject, said sheath for collapsing said object entrapping assembly whenretracted into said sheath, and a handle assembly located at theproximal ends of said sheath and said drive wire, said handle assemblycomprising a base, a sliding portion and a means for rotating the objectentrapping assembly for independent rotational positioning of saidobject entrapping assembly, actuation of said sliding portion relativeto said base enables longitudinal movement of said object entrappingassembly into and out of said sheath, whereby said handle assemblyprovides for independent rotation and longitudinal movement of saidobject entrapping assembly.
 11. The medical retrieval device of claim 10further including a thumb pad for actuating said sliding portion, atleast some portion of said thumb pad will overlap said base at somepoint during longitudinal actuation of said sliding portion.
 12. Themedical retrieval device of claim 10 wherein length of said sheath isabout 50 centimeters or greater and at least some of said sheath has anoutside diameter of approximately one millimeter or less.
 13. Themedical retrieval device of claim 10 wherein said base has a lengthbetween 5 cm and 20 cm.
 14. The medical retrieval device of claim 10wherein said rotational means is a spinner having a maximum diameter of1.5 cm or less.
 15. The medical retrieval device of claim 10 whereinsaid longitudinal movement of said sliding portion relative to said baseis 5 cm or less.
 16. The medical retrieval device of claim 10 whereinsaid drive wire is formed of nickel titanium.
 17. A medical devicecomprising: a handle assembly comprising an elongate base having aproximal end, a distal end and a longitudinal slot, a sliding portionengaged with said slot, a spinner rotatably attached to the proximalend, and a sheath and a drive wire, said sheath fixed to said slidingportion and said drive wire fixed to said spinner, whereby rotation ofsaid spinner with respect to said elongate base rotates said drive wirewith respect to said sheath.
 18. The medical device of claim 17 furthercomprising an object entrapping assembly connected to said drive wire.19. The medical device of claim 17 wherein said sliding portion haslongitudinal travel relative to the base of 5 cm or less.
 20. Themedical device of claim 17 wherein said spinner comprises an axiallypositioned knob having a maximum diameter of 1.5 cm or less
 21. Themedical device of claim 17 wherein the base limits rotational movementof said sliding portion.
 22. The medical device of claim 17 wherein thebase limits longitudinal movement of said spinner.